Firearm ejector mounted on a movable chamber extension



A. s. YEOMANS. JR- FIREARM EJEICTOR MOUNTED ON A MOVABLE Aug. 9, 1960 CHAMBER EXTENSION Filed July 19, 1957 TOE INVENTOR. ARTHUR S. YEOMANS JR .l. K x f//// 7/////////////// a J \M: E

United States Patent Ofiice 2,948,075 Patented Aug. 9, 1960 FIREARM EJECTOR MOUNTED ON A MOVABLE CHAMBER EXTENSION Arthur S. Yeomans, In, North Haven, Conn, assignor to Olin Mathieson Chemical Corporation, a corporation of Virginia Filed July 19, 1957, Ser. No. 672,906

2 Claims. (CI. 42-25) The present invention relates to firearms and in particular to ejectors for firearms of the type utilizing the movable chamber principle.

The movable chamber firearm is a well-known type and incorporates a chamber unit which is separate from the barrel and is movable from a firing position wherein a bolt and the chamber are locked together to a recoil position. During recoil sufficient kinetic energy is developed in a release mechanism to unlock the bolt from the chamber.

A firearm disclosing and explaining the movable chamber feature and its cooperation with a breech bolt is shown and described in US. Patent No. 2,476,232 to D. M. Williams dated July 12, 1949.

In the Williams firearm the breech block or bolt is normally urged forwardly into a closed position in which the bolt is interlocked with the chamber unit in a firing position. The bolt is held securely in this position by making a wedging engagement with an extension formed .on the chamber unit.

The bolt is unlocked when the movable chamber unit is thrust towards the butt of the firearm by the recoil of firing. The moving chamber unit in turn imparts kinetic energy to the bolt and a pair of slides which make a lost motion connection with the bolt.

Initially the bolt, the slides and the chamber unit move to the rear as an assembly. Thereafter, the chamber unit and the bolt are stopped. A lost motion connection between the bolt and the slides permits the slide to overdrive or pass the bolt and chamber unit.

After a suitable dwell interval, a follower carried by the slide is effective to cam the bolt free of the chamber unit, whereupon the slide imparts kinetic energy to the bolt effective to carry it to a fully opened position.

Since the bolt carries an extractor, a spent shell is hauled out of the chamber when the bolt begins to move relative to the chamber. The shell remains connected to the bolt and the two elements move rearwardly as a unit.

The present invention takes advantage of the relative motion that occurs between the bolt and the chamber unit to achieve ejection of the spent shell.

To this end an ejector lug is formed on the inside of the chamber extension which is effective when the assembled bolt and spent shell pass the lug to pivot the shell about the extractor casting it free of the firearm.

A particular feature of the present invention is the provision of a novel ejector mechanism in combination with a firearm utilizing the Williams movable chamber principle.

Another object of the present invention is to provide a simple ejector for a firearm where the ejector is mounted on a movable member.

Another feature of the present invention is the provision of an ejector in a firearm utilizing the Williams movable chamber feature where the relative motion inherent in a Williams action is utilized to accomplish ejection.

A firearm embodying certain features of the present invention may comprise a receiver, a chamber unit including a chamber and a chamber extension, a pair of slides movable within the receiver, a bolt carried by the extension, cam means connecting the slide, the bolt and the chamber unit together so as to be movable initially as an assembly and operative to permit relative motion to occur between the bolt and the chamber unit and ejector means mounted on the chamber extension effective to engage the head of a spent .shell carried by the bolt to eject the shell whenever relative motion occurs between the bolt and said chamber unit.

Other features and advantages of the present invention will become more apparent from the succeeding .specification when read in conjunction with the appended drawings wherein:

Fig. 1 is a fragmentary view, partly in elevation, of a firearm embodying the principles of the present invention;

Fig. 2 is an elevational view of the movable chamber unit of the Williams design and showing to advantage the location of the ejector thereon;

Fig. 3 is a fragmentary view, in section, of a portion of the chamber unit of Fig. 2 as viewed in the plane 33;

Fig. 4 is an elevational view of the bolt, and;

Fig. 5 is an end view from the left side of the bolt of Fig. 4 showing to advantage a clearance slot formed in the bolt.

Referring now in detail to the single sheet of drawings there is shown a barrel 10 connected to a receiver 11.

In the manner of said Williams patent, a chamber unit, indicated generally by the reference numeral 12, is disposed within the receiver and the barrel. The unit comprises a chamber element 13 having a cartridge 14 disposed therein and is formed with an extension 16.

As is apparent in Fig. 1, abolt 17 having an extractor 18 is shown in the firing position wherein the bolt is snugly wedge against the extension 16 as at 15.

As shown and described in said Williams patent, the bolt is carried by and is pi-votally connected to a pair of slides 20 (only one shown) by means of a pin 21. The slides are in turn carried by the receiver 11.

Upon firing the cartridge 14 in well known manner, the recoil which attends the firing imparts kinetic energy to the chamber unit and the interlocked bolt whereupon these elements move as a unit to the rear or to the left as viewed in Fig. 1 through a relatively short distance as represented by the space 19.

The initial motion of the unitary assembly comprising the chamber unit and the bolt also imparts kinetic energy to the slides 20 wherein the ends 25 of the cam slot 22 are in contact with .the pin 21 carried by the slides. Thus, the chamber unit, the bolt, and the slides move, initially, as an assembly.

After the motion of the chamber unit and the bolt is arrested, the slides 20 carrying the pin 2-1 have received sufficient kinetic energy to continue moving to the left, as viewed in Fig. 1. In effect, the slide and the pin 21 overdrive or pass the interlocked bolt and chamber unit as they proceed along the flat portion 23 of the cam 22. When the pin 21 encounters the inclined surface 24 of the cam slot the bolt is hauled downwardly and out of wedgin-g engagement with the chamber extension 16 with the result that kinetic energy is now imparted to the bolt through the pin 21. At this time the bolt proceeds to move relative to the chamber unit. The bolt is provided witha cut out portion 26 to provide clearance as it moves past an ejector lug 27 formed on the inside of the chamber extension.

In well known manner, the extractor 18 carried by the bolt 17 engages. the head 28 of the cartridge 14 so that when relative motion occurs between the bolt and the chamber unit, the spent cartridge is hauled out of the chamber 13 and proceeds to the left. As the bolt moves. past the ejector 27 and continues to the left, as viewed in l and 2',fthe spent cartridge is carried along until ultimately the rim 31 of the cartridge, shown in dotted lines in Fig. 2, is engaged by the lug 27.

Continued motion of the bolt to the left is elfective to cause the cartridge to be pivoted about the extractor as a result of the lever action generated when the rim 31 is abruptly stopped bythe ejector lug 27. Sufiicient momentum developed in the spent shell to cast it free of the firearm.

It is to be noted that in prior art arrangements of firearms utilizing the Williams principle, the ejector includes a pin, springs, and other elements disposed in the general location or thedottedlines of Fig. 5 and designated by the reference numeral 29..

Thus, the particular advantages of the ejector of the present invention over prior art structures are (1) simplicity of construction (.2) additional spacing of the ejector from the center line of the bolt provides increased leverage and (,3) a considerable number of piece parts and manufacturing operations are eliminated.

While a specific embodiment of the present invention is disclosed and described, it is evident that many variations may be devised as considerations ofv design and cost of manufacture dictate without departing from the spirit and scope of the present invention.

What is claimed is:

1. In a. firearm including a receiver, a movable ohamber unit having a chamber and a chamber extension, a pair of. slides. movable within the receiver, a bolt carried by the extension, cam means connecting the slides,

the bolt and the chamber extension operative to efiect a lost motion connection between the bolt and the chamber .unit whereby the bolt is movable relative to the chamber unit, the improvement comprising: ejector means mounted on the movable chamber extension effective to engage the head of a spent shell to eject the shell Whenever relative motion occurs between the bolt and said unit the mobility of said chamber being efiective to cushion impact between the spent shell and said ejection means.

2.. In a firearm including a receiver, a. movable chamber, a pair of slidesJmova'ble within the receiver, a bolt carried by and locked to the chamber, pin means conmeeting the slides and the bolt, cam means formed integral with thebolt and cooperating with the pin to unlock the bolt and to move the 'bolt relative to the chamber, the improvement comprising: ejector means mounted on the movable chamber efliective to engage the head of a. spent shell to eject the shell whenever relative motion: occurs between the bolt and said extension the mobility of said chamber being effective to cushion impact occurring between the spent shell and said ejection means.

References Cited in the file of this patent UNITED STATES PATENTS 2,845,740 Simmons -e Aug. 5, 

